Bonsai: add category-level select-all to the Drawings list (#8826)

Add an "Is Selected" checkbox to each target-view category header in
BIM_UL_drawinglist that toggles selection for all drawings in the
category. The toggle only affects drawings currently visible in the
list (honoring the show_drawings_on_sheets_only filter), and the header
checkbox reflects the aggregate selection state of its drawings.

Also make category headers more obvious: wrap them in a box() for a
distinct inset background and make the header name clickable to
expand/contract the category (same as the disclosure triangle).

Ref: #8825

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

src/bonsai/bonsai/bim/module/drawing/__init__.py

@@ -108,6 +108,7 @@ classes = (
     operator.SelectAssignedProduct,
     operator.SelectSimilarTextLiteralValue,
     operator.ToggleTargetView,
+    operator.ToggleDrawingCategorySelection,
     operator.OpenDocumentationWebUi,
     operator.FilterSelectedObjectsIfIntersectedByCamera,
     prop.Variable,

src/bonsai/bonsai/bim/module/drawing/operator.py

@@ -3874,6 +3874,26 @@ class ToggleTargetView(bpy.types.Operator):
         return {"FINISHED"}
 
 
+class ToggleDrawingCategorySelection(bpy.types.Operator):
+    bl_idname = "bim.toggle_drawing_category_selection"
+    bl_label = "Toggle Category Selection"
+    bl_description = "Select or deselect all drawings in this view category"
+    bl_options = {"REGISTER", "UNDO"}
+
+    target_view: bpy.props.StringProperty()
+
+    if TYPE_CHECKING:
+        target_view: str
+
+    def execute(self, context):
+        drawings = tool.Drawing.get_visible_drawings_in_category(self.target_view)
+        # If everything visible in the category is already selected, deselect all; otherwise select all.
+        new_state = not all(d.is_selected for d in drawings)
+        for drawing in drawings:
+            drawing.is_selected = new_state
+        return {"FINISHED"}
+
+
 class ExpandSheet(bpy.types.Operator):
     bl_idname = "bim.expand_sheet"
     bl_label = "Expand Sheet"

src/bonsai/bonsai/bim/module/drawing/ui.py

@@ -874,8 +874,8 @@ class BIM_UL_drawinglist(bpy.types.UIList):
             layout.label(text="", translate=False)
             return
 
-        row = layout.row(align=True)
         if item.is_drawing:
+            row = layout.row(align=True)
             row.label(text="", icon="BLANK1")
             selected_icon = "CHECKBOX_HLT" if item.is_selected else "CHECKBOX_DEHLT"
             row.prop(item, "is_selected", text="", icon=selected_icon, emboss=False)
@@ -896,6 +896,9 @@ class BIM_UL_drawinglist(bpy.types.UIList):
                     item.ifc_definition_id
                 )
         else:
+            # Give category headers a distinct inset background so they stand out from drawing rows.
+            box = layout.box()
+            row = box.row(align=True)
             if item.target_view == "PLAN_VIEW":
                 icon = "UV_FACESEL"
             elif item.target_view == "ELEVATION_VIEW":
@@ -916,7 +919,19 @@ class BIM_UL_drawinglist(bpy.types.UIList):
                 op = row.operator("bim.toggle_target_view", text="", emboss=False, icon="DISCLOSURE_TRI_RIGHT")
                 op.target_view = item.target_view
                 op.option = "EXPAND"
-            row.prop(item, "name", text="", icon=icon, emboss=False)
+            group = tool.Drawing.get_visible_drawings_in_category(item.target_view)
+            all_selected = bool(group) and all(d.is_selected for d in group)
+            row.operator(
+                "bim.toggle_drawing_category_selection",
+                text="",
+                icon="CHECKBOX_HLT" if all_selected else "CHECKBOX_DEHLT",
+                emboss=False,
+            ).target_view = item.target_view
+            row.separator(factor=0.5, type="SPACE")
+            # Clicking the header name toggles expand/contract, same as the disclosure triangle.
+            op = row.operator("bim.toggle_target_view", text=item.name, icon=icon, emboss=False)
+            op.target_view = item.target_view
+            op.option = "CONTRACT" if item.is_expanded else "EXPAND"
 
     def filter_items(self, context, data: DocProperties, propname: str):
         drawings = getattr(data, propname)

src/bonsai/bonsai/tool/drawing.py

@@ -2908,6 +2908,29 @@ class Drawing(bonsai.core.tool.Drawing):
                 result.add(drawing.id())
         return result
 
+    @classmethod
+    def get_visible_drawings_in_category(cls, target_view: str) -> list[DrawingProperties]:
+        """Get the drawing items in a target view category that are currently visible in the drawing list.
+
+        Grouping is positional: individual drawing items don't carry their own ``target_view``, they belong to
+        the most recent header item above them. Only expanded categories contribute drawing items to the
+        collection, so a collapsed category yields an empty list. Respects the ``show_drawings_on_sheets_only``
+        filter so that select-all only affects visible drawings.
+        """
+        props = cls.get_document_props()
+        drawings: list[DrawingProperties] = []
+        in_category = False
+        for item in props.drawings:
+            if not item.is_drawing:
+                # Header row: we're inside the requested category until the next header.
+                in_category = item.target_view == target_view
+            elif in_category:
+                drawings.append(item)
+        if props.show_drawings_on_sheets_only:
+            sheeted_ids = cls.get_sheeted_drawing_ids()
+            drawings = [d for d in drawings if d.ifc_definition_id in sheeted_ids]
+        return drawings
+
     @classmethod
     def get_camera_matrix(cls, camera: bpy.types.Object) -> Matrix:
         matrix_world = camera.matrix_world.copy().normalized()